Stephen Hawking’s Final Paper Questions Infinite Multiverse Theory

The late Stephen Hawking’s last paper, published Wednesday in the Journal of High Energy Physics, attempts to reign in the multiverse theory, a theory the physicist considered unwieldy and unprovable.

“We are not down to a single, unique universe, but our findings imply a significant reduction of the multiverse, to a much smaller range of possible universes,” Hawking said, in a Cambridge University press release.

The multiverse theory posits that our immediate universe is simply a small pocket of a seemingly infinite mosaic of parallel universes. The theory is based on the idea that much of the universe kept expanding, infinitely, in the wake of the Big Bang, and only in small bubbles did expansion slow down and allow a physical order to be established.